1. Field of the Invention
The present invention relates to a solid-state imaging device and an electronic camera equipped with the solid-state imaging device.
2. Description of Related Art
Video cameras and electronic cameras are among the most popular consumer electronic products used by ordinary consumers today. These cameras are equipped with solid-state imaging devices such as CCD sensors and CMOS sensors. Such a solid-state imaging device includes a plurality of pixels, which generate signal charges in correspondence to the quantity of incoming light, disposed in a matrix pattern. The signal charges having been generated at the individual pixels or electrical signals corresponding to the signal charges are output to an external recipient device via vertical signal lines or the like, each installed in correspondence to a pixel column, in conformance to a drive signal output from a scanning circuit in response to an instruction issued by a timing signal generator.
A camera in the known art may be capable of providing a live view display of a subject image captured via a solid-state imaging device such as that described above by bringing up on display a real-time motion picture of the subject image at a liquid crystal monitor (see Japanese Laid Open Patent Publication No. 2007-184912). In addition, there is a solid-state imaging device known in the related art that includes column A/D conversion circuits, each provided in conjunction with one of the vertical signal lines and digitizes output signals through column A/D conversion executed in correspondence to each pixel column so as to speed up the output process (see Japanese Laid Open Patent Publication No. 2005-86224).
The resolution of the liquid crystal monitor at which the live view display is brought up in the camera is often lower than the resolution of the solid-state imaging device. If such is the case, the live view display cannot be provided by directly utilizing the output signals from a solid-state imaging device adopting the structure disclosed in patent reference literature 2, but rather, signal composition processing or the like must be executed to combine the output signals from the various pixels in correspondence to the resolution of the liquid crystal monitor, which may increase the processing load on the camera when the live view display is to be brought up. In other words, unless signals optimal for the live view display are output at high speed from the solid-state imaging device, the live view display processing load will inevitably increase.